Technical Field
The present invention relates to operate an electronic device in a low-temperature environment, and more particularly, to a heating circuit, an electronic apparatus, and a method for entering an operation mode in a low-temperature environment.
Related Art
In a low-temperature environment, for example, an environment at a temperature lower than −20° C., a part of electronic components in an electronic apparatus cannot operate normally, and even be damaged in operation. Especially for a fluid dynamic bearing in a common hard disk driver, in the low-temperature environment, a viscous liquid film in the fluid dynamic bearing is likely to be solidified. When the viscous liquid film in the fluid dynamic bearings is solidified, if the disk of the hard disk driver rotates, the disk may be damaged, and data stored in the hard disk driver is damaged.
A rugged electronic apparatus, such as a rugged laptop computer, has one or more built-in heaters for heating the hard disk driver or the battery in the rugged electronic apparatus. The purpose of heating the hard disk driver or the battery is to maintain the viscous liquid film or the electrolyte in the fluid dynamic bearing in a liquid state without being solidified. Before booting up, such an electronic apparatus allows the user to turn on the heaters manually, so as to heat the aforementioned electronic components and then switch the electronic apparatus to boot up after a period of heating.
Theoretically speaking, heating the hard disk drivers by multiple heaters simultaneously, the electronic apparatus can boot up as soon as possible. In fact, the average electric power obtained by each heater from the power supplier is reduced when the number of the heaters is increased; therefore, a heating efficiency of each hard disk driver is reduced.